Some vets and shelters treat heart worm with a slow kill method now that basically just entails giving the dog heartworm preventative. It kills off the baby worms in the bloodstream so the infection doesn't get any worse, but can't actually kill off the adult worms already in the heart. With this type of treatment, the adult worms do eventually die off on their own, but it takes, if I remember correctly, about 2 years.
Not every dog can be treated that way though. You'd have to get Xrays and see how badly the dog is infected first. The slow kill method is usually only used with dogs who have very very low level infections, and you should definitely still have the dog monitored by a vet!
If the meds online are legit, and cheaper, maybe your friend could ask their vet if they would be okay with her buying the meds online, but having the vet administer/monitor the dog still.
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.